1. Field of the Invention
The present invention relates to a power source system for a vehicle which has a generator and a power control unit.
2. Description of the Related Art
When a vehicle equipped with a generator runs uphill or increase the speed, sufficient driving power can not be provided without pressing the accelerator pedal or shifting down the transmission gear. This is an obstacle to improve fuel consumption and drivability.
JP-A-5-300668 proposes a system, in which the operation of a generator is stopped when a vehicle runs uphill to improve fuel consumption and drivability.
However, when the operation of the generator is stopped, the voltage applied to various electric loads, such as head lamps and a blower motor for an air conditioner, decreases. This dims the head lamps and reduces quantity of the cooling air.